In case of emergency, what does the term "souls on board" refer to?

The term "souls on board" specifically refers to the total number of people on an aircraft, which includes both passengers and crew members. In emergency situations, this information is crucial for air traffic controllers and emergency response teams as it helps them assess the situation and plan an appropriate response. Knowing the exact number of individuals on the aircraft allows for better management of resources and ensures that necessary precautions and measures are taken to ensure everyone's safety. This terminology emphasizes the human aspect of air travel and highlights the importance of accounting for all individuals involved in any aviation incident.